The budget for Oliver Stone's forthcoming movie about the September 11 attacks, starring Nicolas Cage, is $60m (about £33m). So it does not bode well that Paramount Pictures, the studio behind it, is worried that a 12-minute student art project, distributed free on the web, might be confused with the real thing.

But that is the logic behind a copyright infringement lawsuit Paramount has filed against Chris Moukarbel, 28, who graduated from Yale University last month.

He made the movie with student actors using a bootleg version of Stone's script for World Trade Center, which tells the story of two port authority police officers who were trapped but then escaped from the rubble of the twin towers.

The lawsuit alleges that it is "virtually identical" to the original in its "dialogue, plot, setting, characters and theme".

It is a "poor quality copy", Paramount acknowledges - yet "large numbers of people will see the Moukarbel film first for free and determine ... that they do not want to pay to see the remainder of the WTC film at a theatre when it is released".

Amateur film projects based on Hollywood releases are widely available online, though usually they escape legal problems because the movie in question has already been shown in cinemas. World Trade Center is not due to be released until August,

By yesterday Mr Moukarbel had removed his film, Points of Departure, from his website. "This artwork was created as a commentary on the memorialisation of a particularly historic moment," he said, adding he had "never intended to profit from this artwork, and never have profited from it". Paramount's suit did not specify a figure for monetary damages, but said it wanted a permanent injunction preventing Mr Moukarbel from distributing the film.